Add option to disable login and password routes [#3469083]

Problem/Motivation

A common requirement for using external authentication providers is to disable local authentication.

The OpenID Connect module configuration lets us override the login form, but does not handle the password reset routes, nor the user.login.http route.

Steps to reproduce

Proposed resolution

Add option to disable routes:

user.login.http
user.pass
user.pass.http

Remaining tasks

User interface changes

API changes

Data model changes

Issue fork oktaplus-3469083

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3469083-disable-routes changes, plain diff MR !6
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